Valve will release free Portal 2 downloadable content titled "Perpetual Testing Initiative" for PC and Mac on May 8, the publisher said today.

Valve says you'll be able to "easily create, share, and play Portal 2 puzzles" with the new DLC, which lets you publish maps directly to Steam. Other players will be able to browse, vote, and download user-created maps to play in their own versions of the game.